Validator Chain

The validator chain is the deterministic sequence the referee runs across every Defendable Run. It is rule-only — no model is called on the chain. Each stage either passes or raises a flag; a critical flag (high tier) at any stage caps the verdict at propolis.

The five-stage chain

1. Structure   →  required sections present
2. Schema      →  fields obey declared types
3. Math        →  re-derive every claimed number from the agent's own inputs
4. Evidence    →  required fields non-empty · assumptions labeled · missing inputs disclosed
5. Policy DSL  →  declared gates (e.g. DSCR >= 1.20) evaluated against the agent's own numbers

Each stage is governed by the Flight Sheet’s eval_spec. The full operational detail lives in Rulebook Engine.

Each stage in one line

Stage	What it checks	Tier on flag
Structure	required_output_schema.required keys are all present.	high (missing = false-honey risk)
Schema	Each field’s value obeys the declared type / enum / shape.	high
Math	Every calculations[] result is recomputed via the safe AST evaluator and compared to the claimed result within tolerance. Variable penalty by magnitude.	low / mid / high (by spot of the foul)
Evidence	Required evidence fields non-empty; assumptions labeled; missing inputs disclosed.	mid (typical)
Policy DSL	Declared gates expressed in the DSL ({calc}/{field}/{len}/literal operands; == != >= <= > <, in, all_nonempty, and, or, not, if ops) evaluated against the agent’s own numbers. Missing operand → skip (never false-flag).	declared per rule

What’s NOT on the chain

• No LLM call. The chain is pure code + math.
• No external service call for verification (no third-party fact-checker, no chain anchor). Receipt verification is client-side WebCrypto over the per-org hash chain.
• No silent skips. Every declared check key must be implemented by the engine. If a Flight Sheet references an unknown check key, the engine refuses to load the sheet — a silently-skipped check is a false honey.

Why this matters

Every stage is declarable on the Flight Sheet and verifiable by re-running the engine. The verdict is reproducible: the same Flight Sheet + the same submission → the same verdict, every time. That is the trust boundary. Model assistance lives outside this chain, advisory only, never on the receipt path.

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🐝 Five stages · all code · all reproducible. To the shed.